.net - Convert DataTable To Linq?

Feb 10, 2010

I'm trying to convert DataTable to Linq using

DIm result = From r in dt.AsEnumerable()
Select new ( col1 = r.Field<integer>("id"), col2 = r.Field<string>("desc"))

But i get error near 'new (' saying type expected.

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Convert A LINQ Query Resultset To A DataTable?

Jul 20, 2010

How can i write this query with LINQ to a FoxPro database?SELECT count(*) FROM Table group by item1I wrote it as below, but it doesn't work

Dim Query
Dim dt As New DataTable
Dim da = New Odbc.OdbcDataAdapter("SELECT * FROM table1",connection)

[code].....

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LINQ To DataSet - Convert EnumerableRowCollection Into DataTable

Mar 2, 2012

I am trying to convert my EnumerableRowCollection into a DataTable, but I can't see the CopyToDataTable method. The enm.CopyToDataTable() has the blue saw tooth line under it with error saying " 'CopyToDataTable' is not a member of 'System.Data.EnumerableRowCollection' ". I have set a Reference to System.Data, System.Data.Linq, and System.Data.DataSetExtensions. I thought the CopyToDataTable method was part of the System.Data.DataSetExtensions, right? Anyone know why I can't access this method?

[Code]...

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Convert A Datatable Using A Reference Datatable Asp.net?

Apr 26, 2012

I am finding difficulties to convert a datatable to a new datatable using a reference datatable. My question is confusing and I am not good at explaining things so I drew a picture (see below).I have two datatables on memory and I need to create the third datatable using the second mapping table for reference. The column names are just for example and it can't be hardcoded.

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C# - Convert Code LINQ To SQL In C # LINQ To SQL In .net?

Jun 27, 2012

How can I convert this code LINQ to SQL in C # LINQ to SQL in Vb.net

[Code]...

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Convert An Object System.Data.Linq.DataQuery To System.Linq.IQueryable?

Oct 21, 2009

How can I convert an object of type System.Data.Linq.DataQuery to System.Linq.IQueryable?I'm working with Visual Basic/Silverlight, and the source code of my query is as follows:

Public Function Get_Cli_Pag() As IQueryable(Of V_Cliente_Pagare)
Dim Qry = From P In Me.Context.Pagares Join C In Me.Context.Codigos On C.Codigo

[code]....

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.net - Load DataTable Using Linq?

Apr 16, 2009

I found the following example on [URL] Unfortunately, I need it in VB and it's using some constructs that neither I nor the automated code converters reciognize. Anyone out there know how this should be written in VB.Net? (the problem spot is the "select new {...")

PeopleDataSet ds = new PeopleDataSet();
using (PeopleDataContext context = new PeopleDataContext())
{

[Code].....

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Converting Datatable To Xml Using Linq?

Apr 24, 2012

I need help converting datatable to xml using Linq. I could do it with hardcoded column names as you can see in my code .. but i need it without hardcoding it ..Example datatable ..My linq query ..

Dim xmlDoc As New XDocument(
From row In dt.AsEnumerable()
From row In dt.AsEnumerable()[code]......

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Datatable Grouping Using Linq?

May 25, 2011

I'm completely dense here, but I'm trying to get some stats from a DataTable. One of the columns in the datatable is called "colour".I need to find out how many of each instance of "colour" are in the datatable.

I'm trying:
Dim q = From p In PGWorkingDataTable _
Group p By p("colour") Into Group _

[code].....

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Error With LINQ To DataTable

Jan 23, 2009

Why does the following code give an error?

[Code]...

If I change the code to remove the second field, as below, then the code does not give an error.

[Code]...

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How To LINQ Datatable Update

Sep 21, 2010

discovered the compact mode of this instructions vs usual code. I found sample code for selecting, etc. from a datatable, transforming a column in a list or array - all operations are "Select"s - readonly.I need to make an simple update on a certain rows (using LINQ) from a DISCONNECTED datatable for which now I'm using this

for each dr as datarow in dtable.Rows
dr("MyField") = 77
next

[code].....

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Join Datatable Using LINQ?

Jan 13, 2011

I have two DataTables:

dt1 - personid, name

dt2 - personid

I want to create a third datatable to include records from dt1 when they are NOT in dt2 using LINQ. In this case, I can bind the third datatable to a dropdownlist.

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Linq With Datatable To Generate A CSV

Jan 21, 2011

Am new to the concept Linq.I created a var where i joined 3 tables to get the data and then bind it in a datatable and create a csv file. Now i want to use an additioanl table in the same variable to be bind with the datatable but my problem is i cant use join here since i dnt have any common col or primary col in this additional table.How do i add this extra table?

[Code]...

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Paging With Linq And DataTable?

Apr 20, 2009

I'm writing a small web app in VB.NET and I would like to do paging for my DataTable in the following function :

Public Shared Function Testing(ByVal KeyWord As String, ByVal CurrentPage As Integer, ByVal PageSize As Integer) As DataTable
Dim db As New BibleDataClassesDataContext

[code].....

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Use Linq To Return A Row In A DataTable?

Jan 24, 2012

Currently, I am using a loop to find the row I want to update.

Public Sub pubsub_SetUserDGVColumnWidth(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewColumnEventArgs)
' update all user settings for the given column

[Code]....

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Find A DataTable Row By Column Value Using LINQ?

Jan 7, 2012

I have a Dynamic DataTable Created at runtime. The Setup is like so

Id | Name | Age
-----------------
3 | Mike | 21
6 | John | 43
8 | Sara | 34

What I am trying to do is come up with a linq statement I could use to find and update specific rows.

Such as a statement to change AGE to '33' WHERE ID = '3'

My code So far is:

-[VB.NET]-
Dim MyRow As DataRow = From column In MyTable.Rows Where column("Id") = 3
MyRow(0)("Age") = 33

But this is not updating my DataTable entry.

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Perform An Aggregation On A DataTable With Linq In .net

Dec 22, 2009

I wish to output an IEnumerable type (dictionary(of T) would be perfect, otherwise a datatable would be acceptable) that provides an aggregation of the data within the datatable.In SQL I would write the query as such: select groupByColumn, sum(someNumber) from myTable group by groupByColumn

In VB.NET the closest I have got to this (achieved using information here) is: dt is a datatable containing two columns, referred to by index in p below Dim q = From p In dt Group p By p(0) Into Sum(p(1)) Select p(0), SumOfNumber = Sum

However I receive error: "Range variable name can be inferred only from a simple or qualified name with no arguments." on the p(0) element. Therefore my question is as follows:How can I resolve this error? How do I process the result (q) as an IEnumerable type? Life isn't made any easier because I'm using Linq in unfamiliar vb.net. Many examples are in C#, but I haven't really come across anything suitable even in C#.

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Use Linq To Fetch Data From Datatable?

Jul 8, 2010

i want to use linq to fetch data from datatable.I have 2 tables in Cache and i want to join these tables then get value from resultset.I pasted Original Sql query and my linq query here.My linq query returns nothing.Where do i miss?My original sql query returns 1 row,but q1 is nothing

[Code].....

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Using Linq Count Function With Datatable?

Aug 2, 2011

I write the code below. I want to make short using linq count.

Dim query0 = From obj In dtAginglist _
Where (obj.Field(Of String)("CurrentStatus") = "Open" Or obj.Field(Of String)("CurrentStatus") = "Acknowledge") _

[Code]....

I try to use code below but it dosen't work with if source is datatable.

Dim orderCounts = From c In customers New With { _
c.CustomerID, Key .OrderCount = c.Orders.Count() }

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VS 2008 - LINQ Group By Datatable

Feb 21, 2012

syntax of the LINQ query to use GROUP something BY something and select some fields of the datatable. i am having a datatable filled with some rows, i am trying to fill the datagridview with the GROUP BY query output of some fields.

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Compare Two Datatable And Delete Some Rows By Linq?

Nov 18, 2010

there is two datatable at some datasetsone of them is tbl1 and fileds is (pcode,points) other table is tbl2 and fields is (pcode,stoped)"pcode" is equal at two tables

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Linq Over Datatable Using Dynamic Library Sample?

Nov 3, 2009

I am looking for sample linq code snippet which uses System.Linq.Dynamic against a datatable.

Dim entities = (From ent In dt.AsEnumerable().Where(String.Format("IsUSFederal == {0}", "true")) _
Select Description = ent("Description"), Acronym = ent("Acronym")).ToList

I am getting an error "there is no accessible Where can be called with these arguments". I have included the DynamicLinq.vb file and the application compiles fine (aside from this error). I have included Imports System.Linq.Dynamic but it doesn't appear to be working.

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LINQ Query To SQL And Temporary Datatable In VB2008?

Feb 18, 2010

I have an SQL table(for example, it have 1 column "kod" with 3 rows:1,2,3 ). To operate it, I used class LINQ to SQL and I create tmp dataset with one table, with one column "col" with values - 2,3,4. To operate with this tmp table i use IEnumerable(T).I want to find only new values in tmp table and write its in SQL table. To find this values, i want to use LINQ query. Queris to each table are worked well. But  query for 2 tables don't work.

Imports System.Linq
Imports System.Data.Linq
Public Class Form1

[code]....

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LINQ To DataTable Error - End Of Statement Expected

Sep 21, 2010

If txtSearchString.Text.Trim <> "" Then
Dim searchString As String = txtSearchString.Text.Trim
Dim results As EnumerableRowCollection(Of DataRow) = From PO In FilterPurchaseOrders().AsEnumerable

[CODE]..............

I am getting this error: error BC30205: End of statement expected.

FilterPurchaseOrders() function returns a datatable.

Whats wrong with the above code?

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Linq To DataTable Not Producing Distinct Values?

Oct 19, 2010

I have a datatable which has been dynamically generated from FoxPro tables using a UNION Select statement. e.g.SELECT * FROM x UNION SELECT * FROM y UNION SELECT * FROM Z ORDER By v_alue1This produces a datatable with about 100 rows, each containing many fields, one of which is c_olor. From this datatable, I would like to select the distinct colors and then output in a dropdown.I have a public class Color which just has one property which I can then use as the DataTextField and DataValueField for the dropdownlist

Public Class Color
Private _c_olor As String
Public Property c_olor() As String

[code].....

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LINQ To DataTable, Finding Duplicate Rows?

Jul 5, 2011

Using the following DataTable:

Dim d As New DataTable()
d.Columns.Add("Product", GetType(System.String))
d.Columns.Add("Value", GetType(System.Double))

[code]....

I'm trying to use LINQ to identify if there are more than one of any type of product. In SQL, this would work something like:

SELECT Product FROM SOME_TABLE HAVING COUNT(*) > 1

I can't for the life of me work out how to do this in LINQ. I was following someone who did something like this:

Dim q = From row In d.AsEnumerable()
Group row By New { column1 = row("Product"), column2 = row("Value") }
Into grp

[code]....

But I get an error when I try to actually use 'q'. how I can make this work?

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Performance Side Linq Or Dataset.Datatable?

Apr 30, 2009

from a performance point of view is it faster to work with linq to sql or dataset.datatable?

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Performing Insert And Update On A DataTable Using LINQ

Jul 12, 2011

I am pretty new to using LINQ and have been trying it out querying my strongly typed DataTable.
I have managed to perform a 'Select' ok but was wondering if someone can point me in the right direction to do Insert and Updates. I'm not sure if LINQ is best doing an insert at all?

My Select code is as follows:

Dim results = From myRow In _dt.AsEnumerable() _
Where myRow.Language_key = Lang And _
myRow.Section_key = SectionKey And _

[Code]....

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Retrieve String Array From Datatable Using Linq?

Oct 27, 2010

I have a datatable with one column, I am trying to retrieve the values in the table into a string array using linq.

Dim dt As DataTable = DataAccessManager.ExecuteSelectQuery(selectStr).Tables(0)
Dim strArr() As String = (From dr As DataRow In dt.AsEnumerable.AsQueryable _
Select dr("MASTERID").ToString()).ToArray()

I get an error "Range variable cannot match name of a member of the 'Object' class"

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Select Distinct Rows From Datatable In Linq

Jul 14, 2010

I am trying to get distinct rows based on multiple columns (attribute1_name, attribute2_name) and get datarows from datatable using Linq-to-Dataset.[code]How to do thin Linq-to-dataset?

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Sort Datatable In .net With Linq By Column Index?

Mar 23, 2012

I need to sort a datatable. I do it with linq this an example

Dim query = From c In dt.AsEnumerable _
Order By c.Field(Of DateTime?)("LastPurchaseDate"), _
c.Field(Of String)("LastName") Descending
Dim dv As DataView = query.AsDataView

But my problem is that i need to sort the fields not by passing the name of the column but the index of that.

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Sql - LINQ Or DataTable When Number Of Fields Unknown

Feb 25, 2010

I have a dynamic query which returns a DataTable. This DataTable will contain a varying number of columns depending on the selection used in the query. I want an efficient way of filtering the records in the DataTable.

For Example The DataTable contains columns : A, B, C and D

I need to query this data at serveral points in my program. At some point I may need records where A=10 and C>40. At another point I may need records where A<10 and D=90 etc.etc. The selects are dymanmic, I do not now what Columns or values are needed until the code is executing.

I could simply use a DataTable Filter and build the selection string dynamically. I have no problem with this. However I was wondering if using LINQ would be more applicable. I am completely new to LINQ and would like to use it but don't know its capabilities.

(At present I am using a DataTable but in future this may change to a collection of Objects)

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Update Columns In Datatable Using Linq Without Condition?

Jun 22, 2011

How to update columns in datatable using linq without conditions. I have an idea that I'm just gonna loop all the data in the datatable but don't know what comes in LINQ.

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VS 2008 Datatable To Class Object Using LINQ

Sep 29, 2011

I have a datatable being returned by my DAL. In my BAL I want to return a class object. So I have a class called BusinessArea that has ID, Description and Active properties. I tried this:

[Code]...

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VS 2008 Query Datatable With LINQ And Set DGV Datasource?

Nov 7, 2011

i need to query the datatable & set the outcome as datagridview controls datasource

vb.net
Private Sub Txt_Search_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Txt_Search.TextChanged
'routine objective:- Filter datatable & set the datagridview datasource

[code]....

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VS 2010 Using LINQ To Filter Data From A Datatable?

Sep 1, 2010

I am wondering if it is possible to filter data from a datatable.Sample datatable

Quote:
Sno CatID Nos
1 XYZ 25

[code].....

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Mar 27, 2012

I have this code that use to sort a datatable.

Dim sortingIndex As Integer = orderby
Dim DataTableNew As DataTable = New DataTable
DataTableNew = dt.Clone
Dim query = (From c In dt.AsEnumerable Order By c.Field(Of String)(sortingIndex) Ascending)
query.CopyToDataTable(DataTableNew, LoadOption.OverwriteChanges)

My problem is that with this method I always need (Of String) for it to work, so the date columns are also managed as Strings witch is the problem. Is there a way to use the correct type so the sorting is based on the type of the column?

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LINQ Join Query On Datatable And Arraylist Error?

Dec 6, 2009

I have a set of LINQ queries filtering original datatable (loaded from Excel file) based on user selections in Comboboxes. Then the result is joined with Arraylist to further filter the set. Arraylist is a simple list of strings.

Query:

If (Samples.Item(0) Is Nothing) = False And Samples.Item(0) <> "All samples" Then
queryResults = From records In queryResults Join samp In Samples _
On records("SAMPNUM") Equals samp _

[Code]....

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VS 2010 LINQ On A DataTable - Are Rows Returned As Reference

Feb 6, 2011

When I query a DataTable using LINQ, are the rows returned as references? Either way, is it possible to control this behaviour, so that rows are either returned as references or as new rows?My guess is that all objects are returned as references by default, since that seems to be the normal behaviour in most programming languages.

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How To Fill A DataTable With A List(Of T) Or Convert A List(Of T) To A DataTable

Nov 26, 2009

I have read many posts on this topic; among them and most recently .NET - Convert Generic Collection to Data Table. Unfortunately, all to no avail.

I have a generic collection of structures :

Private Structure MyStruct
Dim sState as String
Dim lValue as Long
Dim iLayer as Integer
End Structure

Dim LOStates As New List(Of MyStruct) I need to fill a DataTable with this list of structures but have no idea how to go about doing this. I am using vb.net in Visual Studio 2008.

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C# - How To Convert Listview To DataTable

Jun 22, 2012

I have seen many examples of populating a listview from a datatable or converting a datatable to a listview but what I am trying to do is exactly the other way around.

How can I convert/copy the contents of a winform listview to a datatable?

[EDIT]

I have a listview with a context menu where users can multiselect items and choose one of the context menu options, I then loop the selected items and extract each selected row (listview item) and serialize it, instead of doing this I wanted to convert the listview to a datatable then add the datatable to a dataset and serialize the dataset.

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Convert A DataTable To List (of T)?

Apr 28, 2012

convert a dataTable to List(of T).In Vb.net on .Net 3.5 If you know How To or maybe a link of somebody who did it.I check this on c# (from another stack question)

public static IEnumerable<T> ToEnumerable<T>(DataTable dt, Func<DataRow, T> translator)
{
foreach(DataRow dr in dt.Rows)
{

[code]....

but I cant translate Func on .net 3.5?

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Convert Csv Data To DataTable?

Jun 20, 2012

I am trying to import a large array of integers stored as a csv file into a VB.Net DataTable called BeamMap. The .csv file consists only of integers, with a delimiter of ,, no quotes around the data (ie., 1,3,-2,44,1), and an end of line character of line feed and carriage return. All I want to do is get each integer into a DataTable cell with the appropriate rows and columns (there are the same number of columns for each row) and be able to reference it later on in my code. I really don't want anything more than absolutely necessary in the code (no titles, captions, headings, etc.), and I need it to be fairly efficient (the csv array is approx. ~1000 x ~1000).

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Convert Datagridview To Datatable?

May 21, 2012

I managed to Convert a Datagridview to Datatable, Now problem is the programmatically addded Columns Seem to end up at the end of the of the initial table layout[code]...

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Convert Xml File To Datatable?

Dec 31, 2009

i am using following code to convert xml file to datatable but its just creating multiple tables (but without data) and i want tables with data..

Dim myDS As New DataSet
Dim xmlStream As System.IO.StreamReader = New System.IO.StreamReader(Server.MapPath("~xmldoc
esult_availhotel.xml"))[code].....

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